Personnally, I don't feel manipulated by the devs. However, I played many console RPGs where you never have any influence on the story to begin with. At best, when you are offered a choice, it's completely meaningless (like, for example, asking you if you wish to drink the tea that you know is drugged, then making you drink it even when you said no). There's also all those adventure games where you can only solve the puzzles in the single way that the designers decided…

So, when I'm playing a PC RPG, I feel I have much more freedom. When that freedom is more of an illusion in the end, I don't even notice it. What I do notice however is when the game react to the things I did, like the examples IamaGuest pointed out. Of course, I haven't played "The Witcher" yet (got the game, but not the PC that can run it), so maybe in that game there is more of a feeling of being manipulated than is usual in a PC RPG.